Shelf



FIG. 1 is a top, rear, and left side perspective view of a shelf showing our new design;

FIG. 2 is a bottom, front, and left side perspective view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is bottom plan view thereof;

FIG. 5 is a front elevational view thereof;

FIG. 6 is a top plan view thereof;

FIG. 7 is an enlarged right side elevational view thereof; and,

FIG. 8 is an enlarged left side elevational view thereof.

The broken-line disclosure in FIGS. 2, 4, 10, and 12 is for illustrative puurposes only and forms no part of the claimed design. 

The ornamental design for a shelf, as shown and described. 